Dice the salt pork and then run it under a cold tap for 1/2 hour to remove most of the salt. Place a large soup pot over a medium flame and add the olive oil. Add the pancetta and salt pork. Moderate the heat so that the pancetta and salt pork render without coloring. After the meats have rendered for several minutes, add the onions, carrots, celery, chili flake, and Anaheim pepper. Sweat until onions are translucent and vegetables are soft, about five minutes.
Add bouquet garni and chopped garlic. Cook until garlic becomes aromatic. Add the white wine and cook out alcohol for a few minutes. Add the San Marzano tomatoes, clam juice, and the potatoes; turn up the heat so that the broth comes to a simmer. Cook the chowder until the potatoes are cooked through. Remove the chowder from the fire and chill it as quickly as possible. Refrigerate the chowder over-night.
When you are ready to serve the chowder place it back on the fire and bring it to a simmer, hold the soup at that temperature for 5 minutes, before adding the chopped clams. Allow the clams to cook for 3 minutes before serving. Before serving taste the soup for seasoning. Usually there is enough salt in the clam broth and the clams themselves.
Serve the chowder piping hot with a drizzle of extra-virgin olive oil and the soft leaves from the celery as a garnish, if you like.
Reprinted with permission by Executive Chef Micheal Cimarusti of Providence restaurant (Los Angeles, CA)